Is 'nut-free' sunflower seed butter safe for children with peanut allergy?

An acute allergic reaction after ingesting "nut-free" butter containing sunflower seeds in a 5-year-old girl with known peanut allergy was reported in the Medical Journal of Australia last year (MJA 2007; 187 (9): 542-543).

Although allergic reactions to sunflower seed are rare (there have been fewer than 30 published cases), the authors raised concerns about the marketing by online and specialty shops of sunflower seed butter as a safe alternative to peanut butter for those with peanut allergy, because allergic reactions can still occur, possibly through a previously-undiagnosed co-allergy or the development of new sensitisation over time.

Earlier this year, Mimi Tang of the Royal Children's Hospital, Melbourne and Raymond Mullins of the John James Medical Centre, Canberra, disputed the advice in the earlier article, stating that in children with existing allergies, new allergies may develop with time and this risk is unpredictable. In addition, there is little evidence to recommend avoidance of particular foods beyond the age of 6 months as an effective preventive strategy; and parents should not be optimistic that such strategies will prevent new sensitisation once their child has developed food allergy (MJA 2008; 188 (5): 316).